feat: remove fip-0115 feature flag

[LesnyRumcajs]

Summary of changes

Changes introduced in this pull request:

• removed the fip0115 feature flag, see https://github.com/filecoin-project/lotus/pull/13581/changes

Reference issue to close (if applicable)

Closes

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation. All new code adheres to the team's documentation standards,
• I have added tests that prove my fix is effective or that my feature works (if possible),
• I have made sure the CHANGELOG is up-to-date. All user-facing changes should be reflected in this document.

Outside contributions

• I have read and agree to the CONTRIBUTING document.
• I have read and agree to the AI Policy document. I understand that failure to comply with the guidelines will lead to rejection of the pull request.

Summary by CodeRabbit

• Chores

  • Updated devnet infrastructure with latest Lotus release
  • Removed FOREST_FEES_FIP0115HEIGHT environment variable; FIP-0115 now automatically activates at FireHorse network upgrade

• Documentation

  • Updated changelog to reflect FIP-0115 automatic activation behavior

[coderabbitai]

Walkthrough

This PR removes environment-variable-controlled FIP-0115 (FireHorse) activation logic and replaces it with configuration-based network upgrade height. The compute_base_fee function signature is updated to accept a firehorse_height parameter, and all call sites are updated to supply this height from chain configuration. Docker image and Lotus source commit pins are also updated.

Changes

Cohort / File(s)	Summary
Configuration & Deployment CHANGELOG.md, scripts/devnet/.env, scripts/devnet/lotus.dockerfile	Documentation updated to reflect removal of FOREST_FEES_FIP0115HEIGHT env variable; Lotus devnet image and source commit pins bumped to newer versions.
Base Fee Computation Core src/chain/store/base_fee.rs	Removed env-driven FIP0115_HEIGHT toggle and static; added firehorse_height parameter to compute_base_fee function; refactored branching logic to select between utilization-based (pre-FireHorse) and premium-based (post-FireHorse) fee computation based on epoch comparison.
Call Sites src/chain_sync/tipset_syncer.rs, src/message_pool/msgpool/provider.rs, src/rpc/methods/miner.rs	Updated all calls to compute_base_fee to pass both smoke_height and firehorse_height parameters sourced from chain configuration instead of env variables.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• chore: replace placeholder name for NV28 with FireHorse #6942: Introduces Height::FireHorse variant and updates network height mappings, providing the underlying network configuration infrastructure that this PR's code changes consume.
• chore: nv28 skeleton #6706: Adds NV28 skeleton with new upgrade height and wiring into ChainConfig, establishing the configuration layer that sources the firehorse_height values used in this PR's updated call sites.
• feat: impl basefee change from FIP-0115 #6702: Directly parallels this PR's modifications to compute_base_fee signature and call-site updates across tipset_syncer, msgpool provider, and miner, suggesting closely coordinated changes.

Suggested reviewers

• sudo-shashank
• akaladarshi

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The PR title accurately describes the main objective: removing the fip-0115 feature flag, which is reflected across all modified files.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch revert-fip0115-feature-flag

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch revert-fip0115-feature-flag

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[coderabbitai]

🧹 Nitpick comments (1)

src/chain/store/base_fee.rs (1)

219-221: Cover the post-FireHorse branch in this regression test.

This assertion still only exercises the utilization path. Please add a second case with epoch >= firehorse_height so the premium-based path is also protected against bad-input panics.

➕ Suggested test extension

 #[test]
fn compute_base_fee_shouldnt_panic_on_bad_input() {
let blockstore = MemoryDB::default();
- let h0 = CachingBlockHeader::new(RawBlockHeader {- miner_address: Address::new_id(0),- ..Default::default()- });- let ts = Tipset::from(h0);+ let make_tipset = |epoch| {+ Tipset::from(CachingBlockHeader::new(RawBlockHeader {+ miner_address: Address::new_id(0),+ epoch,+ ..Default::default()+ }))+ };
let smoke_height = ChainConfig::default().epoch(Height::Smoke);
let firehorse_height = ChainConfig::default().epoch(Height::FireHorse);
- assert!(compute_base_fee(&blockstore, &ts, smoke_height, firehorse_height).is_err());+ assert!(+ compute_base_fee(+ &blockstore,+ &make_tipset(firehorse_height - 1),+ smoke_height,+ firehorse_height,+ )+ .is_err()+ );+ assert!(+ compute_base_fee(+ &blockstore,+ &make_tipset(firehorse_height),+ smoke_height,+ firehorse_height,+ )+ .is_err()+ );
}

Based on learnings: In src/chain/store/base_fee.rs, the FIP-0115 activation condition uses ts.epoch() >= next_upgrade_height intentionally and matches the Lotus reference implementation in chain/store/basefee.go.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.
In `@src/chain/store/base_fee.rs` around lines 219 - 221, Add a second assertion
in the test that calls compute_base_fee with an epoch at or beyond the FireHorse
upgrade so the premium-based branch is exercised: create a timestamp/TipSet `ts`
whose epoch is >= `firehorse_height` (use
`ChainConfig::default().epoch(Height::FireHorse)` or increment it), then call
`compute_base_fee(&blockstore, &ts, smoke_height, firehorse_height)` and assert
it returns Err (or handles bad input without panicking). Ensure you reference
the same `blockstore`, `ts`, `smoke_height`, `firehorse_height` variables and
the `compute_base_fee` function to add this second case.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.
Nitpick comments:
In `@src/chain/store/base_fee.rs`:
- Around line 219-221: Add a second assertion in the test that calls
compute_base_fee with an epoch at or beyond the FireHorse upgrade so the
premium-based branch is exercised: create a timestamp/TipSet `ts` whose epoch is
>= `firehorse_height` (use `ChainConfig::default().epoch(Height::FireHorse)` or
increment it), then call `compute_base_fee(&blockstore, &ts, smoke_height,
firehorse_height)` and assert it returns Err (or handles bad input without
panicking). Ensure you reference the same `blockstore`, `ts`, `smoke_height`,
`firehorse_height` variables and the `compute_base_fee` function to add this
second case.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro

Run ID: d9e22f25-b578-4632-902a-e05c9a7cad1b

📥 Commits

Reviewing files that changed from the base of the PR and between 462e824 and 3fb1877.

📒 Files selected for processing (7)

• CHANGELOG.md
• scripts/devnet/.env
• scripts/devnet/lotus.dockerfile
• src/chain/store/base_fee.rs
• src/chain_sync/tipset_syncer.rs
• src/message_pool/msgpool/provider.rs
• src/rpc/methods/miner.rs

[codecov]

Codecov Report

❌ Patch coverage is 59.09091% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 63.93%. Comparing base (462e824) to head (3fb1877).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/rpc/methods/miner.rs	0.00%	5 Missing ⚠️
src/chain_sync/tipset_syncer.rs	66.66%	2 Missing and 1 partial ⚠️
src/chain/store/base_fee.rs	83.33%	1 Missing ⚠️

Additional details and impacted files

Files with missing lines	Coverage Δ
src/message_pool/msgpool/provider.rs	57.14% <100.00%> (+2.97%)	⬆️
src/chain/store/base_fee.rs	86.19% <83.33%> (ø)
src/chain_sync/tipset_syncer.rs	63.19% <66.66%> (+0.60%)	⬆️
src/rpc/methods/miner.rs	7.53% <0.00%> (-0.16%)	⬇️

... and 3 files with indirect coverage changes

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 462e824...3fb1877. Read the comment docs.

🚀 New features to boost your workflow:

• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.